Active User

After experimenting with a Basic Battery Capacitance Charger (BBCC) I decided to build a better one with more capabilities and options.
Some changes to basic schematic were necessary.

As you can see above, 3 capacitors of values 6, 16 and 20 uF are used in order to have a range of output power.

SW1 SW2 SW3 AMPS
ON OFF OFF 0.2
OFF ON OFF 0.5
ON ON OFF 0.7
OFF OFF ON 1
ON OFF ON 1.2
OFF ON ON 1.5
ON ON ON 2

I have a range of capacitors and high voltage rectifier bridges (removed from computer PSUs)

A dead computer PSU could provide the enclosure for the parts

Guts removed and parts fit nicely inside

Original SPST Switch changed for a DPST so when is OFF both lines (L & N) will be cut off)

I made a rectangle hole for a Voltmeter – Ammeter

This AMMETER can measure up to 300V and 10A, but needs to be powered from 7 to 30 volts DC. So a small transformer 230 to 7,5v AC from an old cell phone PSU had to be modified adding a rectifier and a filter capacitor to provide 12,3V for the AMMETER.

It fits in the box nicely

A metal panel had to be prepared for the 3 rocker switches.

A paper pattern and a few dremel cutting disks later it was ready.

A label will make the box look nicer. It is a printout on special inkjet paper with two coats of clear varnish on top.

And the box is ready

Unfortunately the VOLT-AMMETER I have measures up to 100V so I have to wait for the new one (from ebay) to have the unit fully functional.

Until then I use my multimeter to read the battery voltage.
Thanks for reading

Active User

Pretty simple!
I made a sketch with the dimensions of the face I wanted to cover, the approximate positions of Voltmeter and switches then in Photoshop I created a paper of the same size, the lines I wanted and pasted the Danger sign. (thank you google) Initially I created wide rectangles around switches and voltmeter but as I was not sure I made exact measurements I only left the voltmeter rectangle.

Next I printed it on a "coated" inkjet paper. Plain paper will do also but after varnishing it turns out a little grayish!

To be on the safe side I dublicated the original sketch and pasted a few more danger signs
Then I sprayed with clear varnish on both sides and let it dry.
The printout hanging after spraying to dry

After drying I cut it to size, put it on the box cut all openings tested switches and voltmeter.
Testing label on the box.

And Finally it was a matter of some glue spray on the metal and fixing the paper in place (well its no longer paper it resembles plastic) on the metal

Active User

I followed plans once for a de-sulfator and it used a fly-back inductor that was switched by a MOSFET and a 555 timer. The output was around 50-60 volts DC and it worked well on several old batteries. The theory was the intermittent high-voltage pulses from the collapsing field didn't over heat the battery but burned through the sulfation. Your circuit puts high voltage DC on the battery continuously. Will it overheat? Do you use a timer to control time on?

Active User

I followed plans once for a de-sulfator and it used a fly-back inductor that was switched by a MOSFET and a 555 timer. The output was around 50-60 volts DC and it worked well on several old batteries. The theory was the intermittent high-voltage pulses from the collapsing field didn't over heat the battery but burned through the sulfation. Your circuit puts high voltage DC on the battery continuously. Will it overheat? Do you use a timer to control time on?

Charging starts with high voltage and in a matter of minutes drops to normal. On test It overheated some Sealed Lead Acid batteries (SLAs) that had some cells shorted. Overheated the particular cells not the whole battery. There was no problem on other SLAs (just warm in touch) and no heat at all on motorcycle Wet Cell ones (capacity 8 AH). I had not tested bigger capacity ones yet as I have to travel some 30 miles to get my old ones.
I use no timer as I constantly monitor the voltage not to let it exceed 15.3V.